vulnerability
MFSA2025-32 Thunderbird: Security Vulnerabilities fixed in Thunderbird 128.10 (CVE-2025-4091)
| Severity | CVSS | Published | Added | Modified |
|---|---|---|---|---|
| 9 | (AV:N/AC:M/Au:N/C:C/I:C/A:C) | Apr 29, 2025 | Apr 30, 2025 | May 10, 2026 |
Severity
9
CVSS
(AV:N/AC:M/Au:N/C:C/I:C/A:C)
Published
Apr 29, 2025
Added
Apr 30, 2025
Modified
May 10, 2026
Description
Memory safety bugs present in Firefox 137, Thunderbird 137, Firefox ESR 128.9, and Thunderbird 128.9. Some of these bugs showed evidence of memory corruption and we presume that with enough effort some of these could have been exploited to run arbitrary code. This vulnerability was fixed in Firefox 138, Firefox ESR 128.10, Thunderbird 138, and Thunderbird 128.10.
Solution
mozilla-thunderbird-upgrade-128_10
Rapid7 Labs
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